B and C are ur answers
In an atom of an element there are a fixed number of electrons. If the total mass of electrons in 1 mole (6.022 x 1023) of atoms of a certain element is 18.65 mg, how many protons must there be in the nucleus of that atom? (mass of electron = 9.109 x 10–28 g).
Answer:
No. of protons = 34
Explanation:
First we need to calculate the number of electrons in one mole of the the element:
No. of electrons per mole = Total Mass of Electrons/Mass of 1 Electron
No. of electrons per mole = (18.65 x 10⁻³ g)/(9.109 x 10⁻²⁸ g)
No. of electrons per mole = 2.04 x 10²⁵ electrons/mol
Now, we calculate the no. of electrons in 1 atom:
No. of electrons per atom = No. of Electrons per mole/No. of atoms per mole
No. of electrons per atom = (2.04 x 10²⁵ electrons/mol)/(6.022 x 10²³ atoms/mol)
No. of electrons per atom = 34 electrons/atom
Since, the no. of protons in a pure element are equal to the number of electrons. Therefore,
No. of protons = 34
In this exercise we have to use the knowledge of atoms to calculate the number of protons, in this way we find:
Protons will be 34
First we need to reckon the number of electrons fashionable individual blemish of the the place where one feels comfortable:
[tex]electrons \ per \ mole = Total\ Mass\ of \ Electrons/Mass\ of\ 1 \ Electron\\ electrons\ per\ mole = (18.65 * 10^{-3} g)/(9.109 * 10^{28} g)\\ electrons \ per \ mole = 2.04 x 10^{25} electrons/mol[/tex]
Now, we plan on the electrons in 1 smallest part of something:
[tex]electrons\ per\ atom = Electrons\ per\ mole/atoms\ per\ mole\\ electrons\ per\ atom = (2.04 * 10^{25} electrons/mol)/(6.022 * 10^{23} atoms/mol)\\ electrons\ per\ atom = 34 electrons/atom [/tex]
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If the chemical reaction AB + CD ⟶ AD + BC releases heat, what is true of the stored bond energy of the reactants and products? The bonds do not have energy, the atoms release heat. The bond energy of the reactants is the same as the bond energy of the products. The bond energy of the reactants is lower than the bond energy of the products. The bond energy of the reactants is higher than the bond energy of the products.
Answer:
The correct option is the last option
Explanation:
The chemical reaction provided in the question is a double-displacement reaction which is an exothermic reaction (which is the reason for the release of heat). An example of a double displacement reaction and exothermic reaction is the neutralization reaction illustrated below.
HCl + NaOH ⇒ NaCl + H₂O
From the law of conservation of energy, energy can neither be created nor destroyed, hence the total energy in a given system should ordinarily be the same (in the reactants and products), however when energy is released in a reaction (as in the case with an exothermic reaction), it shows there are more bond energy in the reactants than in the products and it is the excess energy that is been released into the atmosphere.
What will be the cost of gasoline for a 4,700-mile automobile trip if the car gets 41 miles per gallon, and the average price of gas is $3.79 per gallon?
Answer:
Idk
Explanation:
Find the gallons needed by dividing total miles by miles per gallon:
4700/41 = 114.634 gallons
Multiply the gallons needed by price per gallon:
114.634 x 2.79 = $319.83 Total
Round the answer as needed.
If gallons were rounded to 115 gallons total cost would be $320.85
$ 434.40
Explanation:41 miles ............ 1 gallon
4700 miles .......x gallon
x = 4700×1/41 = 114.63 gallons
114.63 gallons×$3.79 ≈ $ 434.40
According to Democritus, what is the composition of matter?
Answer:
he composition of matter is invisible particles called atoms.
Explanation:
I'm sure its correct
Answer:
The composition of matter is invisible particles called atoms. ... The root of the word "atom" is atomos, meaning uncuttable.
From Google
Hope I Helped
Calculate the percent composition for each of the elements in Na3PO4. A 5.00 gram sample of an oxide of lead PbxOy contains 4.33 g of lead. Determine the simplest formula for the compound. Balance the following equations by inspection: Cu(N03)2 rightarrow CuO + NO2 + O2 C2H6 + O2 rightarrow CO2 + H2O Mg3N2 + H2O rightarrow Mg(OH)2 + NH3 Magnesium (Mg) reacts with chlorine gas (C12) to produce magnesium chloride (MgC12). How many grams of Mg will react with 2 moles of Cl2? Mg(s) + C12(g) rightarrow MgC12(s) The compound P4S3 is used in matches. It reacts with oxygen to produce P4O10 and SO2. The unbalanced chemical equation is shown below, P4S3(s) + O2(g) rightarrow P4O10(s) + SO2(g) What mass of SO2 is produced from the combustion of 0.331 g P4S3 in excess O2? Nitric oxide is made from the oxidation of ammonia. What mass of nitric oxide can be made from the reaction of 8.00 g NH3 with 17.0 g O2? 4 NH3(g) + 5 O2(g) rightarrow 4 NO(g) + 6 H2O(g) To what volume should you dilute 50.0 mL of 12 M HNO3 solution to obtain a 0.100 M HNO3 solution?
Answer:
1. Percentage composition of: Na = 42%; P = 19.0%; O = 39%
2. Simplest formula of compound is PbO₂
3. (i) 2Cu(NO₃) ---> 2CuO + 2NO₂ + 3O₂
(ii) 2C₂H₆ + 7O₂ ---> 4CO₂ + 6H₂O
(iii) Mg₃N₂ + 6H₂O ---> 3Mg(OH)₂ + 2NH₃
4. 48 g of MG will react with 2 moles of Cl₂
5. 0.288 g of SO2 will be produced from the combustion of 0.331 g P₄S₃ in excess O₂
6. 12.8 g of nitric oxide can be produced from the reaction of 8.00 g NH₃ with 17.0 g O₂
7. The stock acid solution should be diluted to 6000 mL or 6.0 L
Explanation:
The full explanation is found in the attachments below
Which charts or graphs always use axes both labeled with quantitative values and show individual points of data, meaning that each point matches with one value on the x-axis and one value on the y-axis? Check all that apply.
The graphs which use axes both labeled with quantitative values and show individual points of data include:
Scatter plotsLine graphsBar graphs.What is a Graph?Thus is defined as a pictorial representation of data or variables in an organized or definite manner.
The graphs mentioned above always have each point matching with one value on the x-axis and one value on the y-axis.
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Uranium is a type of atom. In special circumstances that usually involve high amounts of energy, uranium can be broken. When this occurs, different pieces of the original atom remain, including a substance called plutonium. Which statement most likely describes plutonium? It will still be uranium, just smaller pieces of uranium. It must no longer be a form of matter. It must be a different kind of atom. It will be different than, but have the same properties as, uranium.
Answer:
It's c
Explanation:
I'm taking the test now on edge.
It must be a different kind of atom statement mostly likely describes plutonium. Hence option C is correct.
What are atoms?It is the smallest unit of matter that possess the properties of the chemical element. It can’t be an independently, they form ions and molecules they both are combine and form large numbers of matters.
Atoms are basically three types: Neutrons, protons and electrons.
In periodic table plutonium is above uranium. Plutonium is more powerful as compared to uranium because it is an isotope and more radioactive.
Almost all of naturally occurring. Uranium 92U238with a half-life of 4.468 x 109 year. Most rest of the natural uranium is92U235.
Uranium is generally used in the process of nuclear fission whereas plutonium is used for the production of nuclear weapons.
It must be a different kind of atom statement mostly likely describes plutonium. Hence option C is correct.
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john has a solution with a pH of 12.21. what is the hydrogen ion concentration of this solution?
Answer:
In this way, ph is determined by hydrogen ion concentration . In the case of neutral solution [H+] =10-7 which we call a ph of 7. This means, for example, that a hydrogen-ion concentration of a solution with a ph of 4 is 10-4 mol/l, meaning it contains 0.0001 mole of hydrogen ion in a solution of 1 liter.
Give two real life applications of chromatography
Answer:
Food testing.
Beverage testing.
Drug testing.
Forensic testing.
Answer:
1. Additive detection
2. Crime scene testing
Question 1 (Multiple Choice Worth 2 points)
(01.01 LC)
The strength of gravitational force is affected by the distance between objects and which of the following?
O Weight
O Speed
O Density
O Mass
A decomposition occurs when you open a can or bottle of soda. Carbonic acid,H2CO3, is in carbonated beverages. It decomposes into carbon dioxide and water. If you leave an open soda can out for a long time, it loses its fizz. Which equation represents the balanced chemical equation for this reaction?
Answer:
H₂CO₃ (aq) → CO₂ (g) + H₂O (l)
Explanation:
Step 1: Write out unbalanced decomposition equation
H₂CO₃ (aq) → CO₂ (g) + H₂O (l)
Step 2: Balance equation
We see that we have 3 oxygens on both sides of the reaction.
We also see that we have 1 carbon on both sides of the reaction.
We also see that we have 2 hydrogens on both sides of the reaction.
Therefore, the chemical equation is balanced.
Was the french revolution driving force behind the metric system?
Answer:
yes, they were
Explanation:
The history of the metric system began in the Age of Enlightenment with notions of length and weighttaken from natural ones, and decimal multiples and fractions of them. The system became the standard of France and Europe in half a century. Other dimensions with unity ratios[Note 1] were added, and it went on to be adopted by the world.
What is the freezing point of an aqueous 1.00 m NaCl solution? (Kf = 1.86 *C/m) (Assume complete dissociation of the salt.)
Answer:
The freezing point is -3.72 degrees Celsius
Explanation:
In this question, by assuming the complete dissociation of the salt, we want to calculate the freezing point of an aqueous 1 M NaCl solution .
We proceed as follows;
Firstly, we write the dissociation equation;
NaCl ——> Na+ + Cl-
So the number of ions present in the dissociation is 2. This means that the Vant Hogg factor also called I = 2
Mathematically;
ΔTf = Kf*m*i
m represents the molality which is given as 1
So by substituting the values, we have;
ΔTf = 1.86 * 1 * 2 = 3.72 degrees Celcius
The freezing point however is 0 - ΔTf = 0 - 3.72 = -3.72 degrees Celcius
Why are alkalis sometimes
described as the opposite of
acids?
Answer: Because Alkalis are bases that can dissolve in water, which can also neutralize acid.
The element X has three naturally occurring isotopes. The isotopic masses (amu) and % abundances of the isotopes are given in the table below. Calculate the average atomic mass of the element in amu. PLEASE HELP ASAP THANK YOU SO MUCH
Answer:
162.35 amu
Explanation:
Let A represent isotope X-159
Let B represent isotope X-163
Let C represent isotope X-164
The following data were obtained from the question:
Isotope >>> Abundance >>> Mass no
A >>>>>>>> 30.60 >>>>>>>> 159.37
B >>>>>>>> 15.79 >>>>>>>>> 162.79
C >>>>>>>> 53.61 >>>>>>>>> 163.92
Average Atomic mass =.?
The average atomic mass of element X can be obtained as follow:
Average atomic mass = [(mass of A × A%)/100] + [(mass of B × B%)/100] + [(mass of C × C%)/100]
= [(159.37 × 30.60)/100] + [(162.79 × 15.79)/100] + [(163.92 × 53.61)/100]
= 48.77 + 25.70 + 87.88
= 162.35 amu
Therefore, the average atomic mass of element X is 162.35 amu
You estimate that you sent 135 texts last week but when you get the bill, it was actually 175. Calculate the percent error
Answer: -40
Explanation: Percent error is calculated by subtracting the value you actually recieved from the literature value (175 in your case) SO your answer should be 135-175=-40.
Which wave has the greatest distance from trough to trough?
Answer:
C.C
Explanation:
Just took the test
A transverse wave is a motion in which all points on a wave oscillate along paths at right angles. Hence, option C is correct.
On a wave, what is the distance from trough to trough?The wavelength is the horizontal distance between two adjacent crests or troughs.
The longest distance a particle goes from rest is to the peak of a crest or the bottom of a trough in a transverse wave. The amplitude of a transverse wave is this distance.
Hence, option C is correct.
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(01.04 LC)
What phase of matter has particles that are held together but can flow past each
other and takes the shape of a container, filling it from the bottom up? (3 points)
1) Gas
2) Liquid
3) Plasma
4) Solid
Which of the following is characteristic of grasslands, but not savannas? a. wide temperature range b. two seasons c. droughts and fires d. wet and dry seasons
Answer:
wide temperature range
Explanation:
Grasslands are ecosystem that covers grass and herbs. It can occur in any type of climates. The rainfall is low in grasslands but it is periodic. The temperature in the summer can exceed 100 degrees Fahrenheit in grasslands.
Savannas is a type of grasslands. It is also known as tropical grasslands. They have average annual temperatures that only vary between 70 and 78 degrees Fahrenheit.
It can be concluded that, out of the given options, that shows the characteristic of grasslands, but not savannas is option (a) " wide temperature range".
Answer: A. wide temperature range
Explanation: Got it correct on the Edgenuity 2020 quiz :)
PLEASE PLEASE ANY CHEMISTRY EXPERT!! HELP NEEDED. See attached.
Determine whether each pair of compounds forms a homogeneous solution when combined. For those that form homogeneous solutions, indicate the type of forces that are involved.
Answer:
Explanation:
1st) one are homogenous because the have the same kind of force 9 London force ) all the hydrocarbons are nonpolar and have a London force between their molecules
so pentane dissolve in hexane (like dissolves like )
2nd ) CBr4 has a tetrahedral shape its a nonpolar compound (London bond )
but the water is polar molecules has a ( hydrogen bond ) its molecular shape (bent shape) . Both do not dissolve in each other because they have a different kinds of bond so they are not a homogenous solution .
3rd) its a homogenous because the water can dissolve the ionic bonds between the Li ( cation ) and (NO3 -1 anion ).
4th ) here we can say alcohol can dissolve in a little amount why ?
pentane has a London force bond Alcohol has two different parts first part has OH making hydrogen bond which cant dissolve in the pentane different kinds of bonds ,and the other part -CH3 has a London force bond that can dissolves easily in the pentaneso one part dissolves but the other part can't dissolve so the two compound are slightly dissolves in each other that which mean its not a homogenous solutionWhat are the similarities and differences between a crystal of molecules and a polymer?
The similarities between crystal of molecules and polymers are;
Both are are composed of regular repeating units of moleculesBoth can be arranged in a definite pattern to give a solid materialDifferences between a crystal of molecules and a polymer are;
Polymers result from long chains of molecules while crystal of molecules results from the aggregation of a fewer number of molecules.molecules polymers are held together by chemical bonds while molecules in crystal of molecules are held together by weak inter-molecular forces.Many molecules occurs as crystals. These crystals of molecules have a well defined shape and are composed of a regular repeating unit of molecules not held together by chemical bonds.
Polymers are formed from small molecules called monomers which are arranged in a regular repeating manner to form macro-molecular structures which sometimes have a high tensile strength.
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2. Report each of the following quantities to 3 significant figures. Use standard notation if possible, or
exponential notation if standard notation won't work.
a. 86,942
f. 56,018
b. 0.00621875
g. 0.003870
c. 107062.03
h. 15.9994
d. 4.00049
i. 12.011
e. 96
j. 2,000
Answer:
a. 86,942 = 8.69x10⁴
f. 56,018 = 5.60x10⁴
b. 0.00621875 = 6.22x10⁻³
g. 0.003870 = 3.87x10⁻³
c. 107062.03 = 1.07x10⁵
h. 15.9994 = 16.0
d. 4.00049 = 4.00
i. 12.011 = 12.0
e. 96 = 9.60x10¹
j. 2,000 = 2.00x10³
Explanation:
Hello,
In this case, rounding off each measurement to three significant figures, considering that if the fourth figure is five or more, the third one is rounded, we obtain:
a. 86,942 = 8.69x10⁴ (four places until the last digit and third digit is not rounded).
f. 56,018 = 5.60x10⁴ (four places until the last digit and third digit is not rounded).
b. 0.00621875 = 6.22x10⁻³ (three places until the first digit and third digit is rounded).
g. 0.003870 = 3.87x10⁻³ (three places until the first digit and third digit is not rounded).
c. 107062.03 = 1.07x10⁵ (five places until the last non-decimal digit and third digit is not rounded).
h. 15.9994 = 16.0 (those consecutive nines round the number to 16.0).
d. 4.00049 = 4.00
i. 12.011 = 12.0
e. 96 = 9.60x10¹ (exponential notation is needed since the number initially has two significant figures so an additional zero is added)
j. 2,000 = 2.00x10³ (three places until the last digit and third digit is not rounded).
Best regards.
Give two examples of rocks composed of only one material.
Answer:
pyroxenite, quartzite, dunite (over 90% olivine), anorthosite (over 90% plagioclase feldspar), marble, chalk, gypsum
Explanation:
which argument best explains the charge of an atomic nucleus
Answer:
An atomic nucleus is positively charged because it is composed of protons.
Explanation:
hope this helps you:)
Answer:
An atomic nucleus is positively charged because it is composed of protons.
Explanation: Just took test on edgenuity
100.0 mL of a 0.500 M solution of KBr is diluted to 500.0 mL. What is the new concentration of the solution
Answer:
0.1 M
Explanation:
The following data were obtained from the question:
Initial volume (V1) = 100 mL
Initial concentration (C1) = 0.5 M
Final volume (V2) = 500 mL
Final concentration (C2) =?
Using the dilution formula C1V1 = C2V2, the new concentration of the solution can be obtained as follow:
C1V1 = C2V2
0.5 × 100 = C2 × 500
50 = C2 × 500
Divide both side by 500
C2 = 50/500
C2 = 0.1 M
Therefore, the new concentration of the solution is 0.1 M
The new concentration of the solution of KBr that was diluted to 500mL is 0.1M
HOW TO CALCULATE CONCENTRATION:
The concentration of solution that was diluted can be calculated using the formula as follows:C1V1 = C2V2Where:
C1 = original concentration (M)C2 = diluted concentration (M)V1 = original volume (mL)V2 = diluted volume (mL)According to this question, 100.0 mL of a 0.500 M solution of KBr is diluted to 500.0 mL. The new concentration can be calculated as follows:0.500 × 100 = C2 × 50050 = 500C2C2 = 50 ÷ 500C2 = 0.1MTherefore, the new concentration of the solution of KBr that was diluted to 500mL is 0.1M.Learn more at: https://brainly.com/question/10720472?referrer=searchResults
Help me please, i’d appreciate it a lot! thank you!❤️
Explanation:
think so it is useful and sufficient for your question
. A certain medication is set to deliver through an IV at a rate of 3.0 mg/min. What is this rate in mg/s?
Answer:
[tex]rate=0.05\frac{mg}{min}[/tex]
Explanation:
Hello,
In this case, considering that 1 min equals 60 seconds, we need to perform the unit conversion as shown below in order to compute the rate on mg/s:
[tex]rate=3.0\frac{mg}{min}*\frac{1min}{60s} \\ \\rate=0.05\frac{mg}{min}[/tex]
Best regards.
An element is an arrangement of atoms in a particular way; True or False?
Answer:
i think it's true because An element is a substance that is made entirely from one type of atom
The value of ΔG°′ΔG°′ for the conversion of glucose-6-phosphate to fructose-6-phosphate (F6P) is +1.67 kJ/mol+1.67 kJ/mol . If the concentration of glucose-6-phosphate at equilibrium is 2.95 mM2.95 mM , what is the concentration of fructose-6-phosphate? Assume a temperature of 25.0°C25.0°C .
Answer:
The concentration of fructose-6-phosphate is 1.50x10⁻³M
Explanation:
Gibbs Free energy, ΔG°, is defined as:
ΔG° = -RTln K
Where ΔG° = 1670J/mol
R is gas constant = 8.314J/molK
T is absolute temperature (25°C + 273.15 = 298.15K)
Thus, equilibrium constant, k, is:
1670J/mol = -8.314J/molK* 298.15K ln K
-0.6737 = ln K
0.5098 = K
K of the reaction:
G6P ⇄ F6P
is:
K = 0.5098 = [F6P] / [G6P]
As [G6P] is 2.95x10⁻³M:
0.5098 = [F6P] / [2.95x10⁻³M]
[F6P] = 1.50x10⁻³M
The concentration of fructose-6-phosphate is 1.50x10⁻³MWhat are the components of the water-based carbon cycle?
Answer:
Carbon gets incorporated into marine organisms as organic matter or structural calcium carbonate.
Explanation:
ur welcome
Carbon gets incorporated into marine organisms as organic matter or structural calcium carbonate.
What is the carbon cycle?The carbon cycle describes how carbon moves between the atmosphere, soils, living creatures, the ocean, and human sources.
Carbon gets incorporated into marine organisms as organic matter or structural calcium carbonate. When organisms die, their dead cells, shells and other parts sink into deep water. Decay releases carbon dioxide into this deep water.
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